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單項(xiàng)選擇題

（） should be tested and adjusted when the boiler survey is carried out.

A.The boiler oil tank
B.The steam pipe
C.The fire side
D.The safety valves

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單項(xiàng)選擇題

Foaming in the steam drum may be caused by （） in a boiler.

A.oxygen in the water
B.poor boiler design
C.density too high
D.excessive steam demand

單項(xiàng)選擇題

Too much air in the furnace of an oil-fired boiler would be indicated by （）.

A.yellowish flame
B.golden yellow flame
C.white flame
D.brilliant white flame

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